Pressure reducing valve



`lune 25, 1935. y T. L. THoRsEN 2,005,813

PRESSURE REDUCING VALVE Filed May 23, 1934 `FIGLI Mz f fZTroRNEY Patented June 2)5, 1935 PRESSURE REDUCING VALVE Thorvald L. Thorsen, Beloit, Wis. Application May 23, 1934, Serial No. 727,018

1 Claim.

My invention relates to pressure reducing valves in which no non-metallic diaphragms or other parts are used, the prime object being a. durable trouble free means for reducing pressures and which can be manufactured at moderate cost on ordinary shop tools. Another object is to provide a fitting in cylindrical form with inlet and outlet at opposite ends that can be placed in a pipe line without offsets. The good appearance of such installation is a further object.

This reducing valve is made in several forms all having essentials in common as described hereinafter and as shown by the accompanying drawing in which Figure 1 shows a form in which the high pressure is opposed by the low pressure acting on the enlarged end of a single piston.

Figure 2 shows a form in which the high pressure is opposed by a spring acting with the low pressure against a one size single piston.

Figure 3 shows a. form in which the piston has two sizes as in Figure 1 and a spring on the low pressure end as in Figure 2 with other variations as hereafter described.

The same numerals are used to designate corresponding parts in all three figures.

Referring first to Figure 1 the cylindrical case, I, has a bore, 2, at the high pressure end and a large bore, 3 at the low pressure end. Into this bore is slidably fitted a single piston, 4, havingtwo diameters to lit bores 2 and 3 respectively. Ports 5 in the piston are supplied with high preslsure fluid through a hole 6 bored axially in from the high pressure end of piston 4. Ports 5 register with ports 1 in case I after the piston has moved away from the closed position, in which it is shown in all figures, and admit high pressure fluid to the annular transfer passage 8 surrounding and outside of the cylinder. Sleeve II is the outer wall of transfer passage 8 and is made fluid tight by its ilt on the outside lof the cylinder wall at each-end and by being drawn tight against shoulder I2 on the cylinder by sleeve nut I3 threaded on the 'low pressure end of the cylinder. Transfer passage 8 is made either by boring out sleeve Il as in Figure 1 or by recessing the outside of the cylinder as in Figure 2 and Figure 3. In either case this is a simple lathe operation and the use of sleeve II permits easy access fordrilling ports 'I and 9 in the cylinder wall.

Ports 9 in-cylinder I register with ports I0 in the piston and deliver iiuid from the transfer passage 8 to the low pressure end of the piston. Ports 9 and I0 and ports 5 and l are all closed when. the piston is at the high pressure end o; its travel. Vent IB to atmosphere prevents pressure trap interfering with free movement of the piston.

Referring to Figure 2 piston 4 is here made of one size to iit a straight bore in case I and the' movement of the piston by the high pressure is opposed by spring Il `and the low pressure acting against that end of the piston. This spring may be chosen to give any desired pressure ratio.

In both Figure 1 and Figure 2 the inlet and outlet connect axially at opposite ends. These reducing valves will therefore install co-axially in pipe lines.

Referring to Figure 3 piston 4 is here made in two sizes as in Figure 1 but with a spring I1 acting against the large end. Ports 5 are in the small diameter of the piston and open by crossing edge I8. The fluid then passes through ports 'I transfer passage 8 and ports 9 and I0 as in Figure 1 and Figure 2. Spring I1 is here made manually adjustable by hand screw I9 mounted in plug 20. The outlet I5 is at one side. Piston 4 in this form has a valve face 2| closingv against a corresponding valve seat of the cylinder. This reduces or prevents leakage at times when very little fluid is being used and low pressure would otherwise tend to build up from leakage.

In operation high pressure fluid enters at end I4 and pushes piston 4 to the right until ports 5 open ports 1 of the cylinder in Figure 1 and Figure 2 or cross edge I8 in Figure 3. The fluid then enters transfer passage 8 and passes thence through ports 9 and I0 to the low pressure side of the piston. When the predeterminedl low pressure has been reached the piston-is moved to close the ports by the low pressure acting on the larger area of the large end of piston 4 as in Figure 1, by acting on the low pressure end of the one size piston as in Figure 2 in addition to the tension of spring I l and by acting on the large end of the two size pistons as in Figure 3 in addition to the tension of spring I1 here made manually adjustable. In all cases the piston is held balanced between the high and low pressure ends.

wider. As less is used these ports close correspondlngly.

I claim as my invention:

In a reducing valve, a cylinder having two coaxial bores, the inlet bore being smaller than the outlet bore, a piston slidably fitting both bores. a connection for supplying high pressure against the small end of said piston, communication from high pressure to low pressure being closed by the fit of the small end of the piston in the small bore when in its closed position and opened by a predetermined movement of said piston, said communication including a passage outside the large bore cylinder formed by a separate sleeve xed to the outside of the body of the cylinder, tted pressure tight at both ends and enclosing a recess between the ends to form said passage.

THORVALD L. THORSEN.

As more fluid is used the pressure falls slightly and the piston moves to open ports 5 

